proposal: psql PSQL_TABULAR_PAGER variable

Hi

I wrote a pspg pager https://github.com/okbob/pspg

This pager is designed for tabular data. It can work in fallback mode as classic pager, but it is not designed for this purpose (and I don't plan do it). Can we enhance a set of psql environment variables about PSQL_TABULAR_PAGER variable. This pager will be used, when psql will display tabular data.

Comments, notes?

Regards

Pavel